Device for transforming on demand a city shoe into a sports shoe and shoes adapted to said device

ABSTRACT

Footwear having a sole and a removable device placed under the sole of the footwear. A peripheral region of the sole and the removable device have male-female engagement portions in opposite regions for retaining the removable device under the sole. At least one of the male-female arrangements is provided on a flexible portion of the removable device. The removable device is provided in the vicinity of at least one of the male-female arrangements. A protruding release tab integral with the removable device can be selectively moved to cause the deformation of the flexible portion and the disengagement of the male-female engagement portions.

The invention concerns a device to convert an ordinary shoe into a sports shoe when so required, and the shoes fitted with this device.

In a particular application envisaged, the shoe is convertible in order to be suitable for the practice of a sport, such as golf or walking on uneven ground, and also to allow one to walk normally on an ordinary surface such as even ground, a floor or a floor covering, or to move in a gymnasium or a dressing room or a reception area, for example, before or after taking part in the sport.

Numerous devices have been proposed, composed of one or two strips equipped with spikes and designed to be attached under the sole and held in position by various means.

U.S. Pat. No. 1,552,512 describes a device composed of a single strip to be applied under the heel, and which has a front wing and a rear wing which fit around and press against the front edge and the rear edge of the heel respectively.

U.S. Pat. No. 2,118,778 describes a device composed of a narrow, u-shaped strip which is placed under the heel and is fixed to it by screws which pass through the wings of the strip and which penetrate into the underside of the heel.

U.S. Pat. No. 6,092,306 describes a device composed of two strips which are attached under the sole, at the front and rear ends of the latter respectively, using lateral tabs which wrap against the sides and the front or against the rear of the sole respectively, so as to clip onto a top edge of the sole.

Publication DE 867 968 describes a device composed of a single U-shaped strip which is applied in the middle zone of the sole between the sole and the heel, and whose wings are equipped with passages for retaining straps.

U.S. Pat. No. 3,713,233 describes a device composed of a single flexible elastic strip attached by an extension to the underside of the heel of the shoe, with this strip being designed to occupy a working position in which the strip is located under the extension, across the shoe, or a retracted position in which the strip is located behind the shoe with the spikes hidden between the shoe and the strip. In this solution, the extension is attached, by gluing or during manufacture, to the underside of the heel, and the strip is equipped with wings designed to be folded against the sides of the shoe and to be attached to these sides by hollow buttons passing in holes in the wings, and attached to screws passing through perforations in the sides of the shoe.

More recently (publication FR 2 831 030), a device has been proposed that is composed of two strips designed to be placed respectively under the forefoot and under the heel, each strip being at some distance from the corresponding end of the sole, thus presenting two longitudinal edges which are positioned across the sole and two lateral edges from which emerge two lateral winglets which fold up against the vertical sides of the sole, where these winglets and the vertical sides of the sole include resources that fit together for the detachable fixing of the strip to the shoe. In the invention described in this publication, the strips are inserted into cut-outs formed in the bottom surface of the sole in order to prevent movement of the strips while walking.

These cut-outs can create problems of differential wear, can shorten the life of the sole, and can increase the production cost of the shoe.

One object of the invention is to overcome drawbacks of the prior art. To this aim, the invention provides a footwear comprising a sole and a removable device placed under the sole of the footwear, a peripheral region of the sole and the removable device having male-female engagement portions in opposite regions for retaining the removable device under the sole, and at least one of said male-female arrangements being provided on a flexible portion of the removable device and said removable device being provided in the vicinity of said at least one male-female arrangement with a protruding release tab integral with said removable device and which can be selectively moved to cause the deformation of said flexible portion and the disengagement of said male-female engagement portions.

In one particular embodiment, the removable device is in the form of a strip.

The strip may be a front strip positioned under the forefoot and having two longitudinal edges and two lateral edges which are shorter than the two longitudinal edges, and has end portions extend upwardly from the lateral edges, the male-female engagement portions of the removable device being positioned in the upper region of the upwardly extending end portions. The two longitudinal edges may not be parallel to each other. The release tab may extend laterally from the end portion of the lateral edge opposite the other foot when the footwear is worn.

The strip may also be a heel strip positioned under the heel and having a back edge and a front edge. The heel strip may includes upwardly extending end portions from the back edge and the front edge. The male-female engagement portions of the heel strip may be positioned at the top of the upwardly extending and portions of the front edge and/or of the back edge. The release tab may extend at the front edge of the removable device toward the front part of the sole.

The mole-female engagement portions may be tongue-recess engagement elements. The tongue-recess engagement elements on the sole may be recesses and tongue-recess engagement elements on the removable device may be claws engaging the recesses of the sole.

The removable device is advantageously made integrally from a flexible material.

The removable device may have on its underside ground anchoring arrangements.

The following are some non-limiting examples of shoes in accordance with the invention, with reference to the figures in the attached drawings, in which:

FIG. 1 is a view in perspective of a shoe for the right foot seen from the left side, with two strips according to the invention in place, under the forefoot and under the heel respectively;

FIG. 2 is a view in perspective similar to that of FIG. 1 after removal of the strips;

FIG. 3 is a view in perspective of the shoe for the right foot of FIG. 1 fitted with the strips, and seen from the left side;

FIG. 4 is a view in perspective of the strip located under the forefoot;

FIG. 5 is a vertical cross-section of the shoe, in the region of the strip located under the forefoot and during the fitting of the strip, seen from the front of the shoe;

FIG. 6 is a section similar to that of FIG. 4, when fitting has been completed;

FIG. 7 shows an example of a dowel;

FIG. 8 is a view similar to that of FIG. 5 in the case of a winglet variant;

FIG. 9 shows an example of a fixing pin;

FIG. 10 shows another example of a dowel;

FIG. 11 is a magnified view of a resource for the attachment of a winglet;

FIG. 12 is a top view of the sole of a shoe for the left foot fitted with strips according to the invention;

FIG. 13 shows a variant of the strips of a device according to the invention;

FIG. 14 schematically shows one phase of the fitting of the device of FIG. 13 to a flat shoe for the left foot;

FIG. 15 schematically shows a flat shoe for the right foot fitted with a device according to FIG. 13;

FIG. 16 shows two views in perspective of a bootee for the right foot PD fitted with a device according to the invention, with the shoe being viewed from the top and the side;

FIG. 17 shows the same shoe as in FIG. 16, but viewed from below and from the right;

FIG. 18 shows the same shoe as in FIGS. 16 and 17, in the process of being fitted out, and

FIG. 19 is a view in perspective of the two strips of the shoes of FIGS. 17 and 18,

FIG. 20 is a view in perspective of another embodiment of a shoe for the right foot seen from the bottom left side, with a front strip and a heel strip according to the invention in place, under the forefoot and under the heel respectively;

FIG. 21 is an exploded view or the bottom part of the shoe of FIG. 20;

FIG. 22 is a close-up view of the front strip;

FIG. 23 is a close-up view of the heel strip; and

FIG. 24 is a view in perspective of the shoe of FIG. 20, seen from the bottom front side of the shoe.

The ordinary shoe for the right foot PD shown in FIGS. 1 to 3 is equipped with two spike-bearing strips 2, 3 under the forefoot 4 and under the heel 5 respectively, surface-mounted on the underside of the sole S in FIG. 12, at some distance from the ends of the sole.

The strip 2 located under the forefoot (FIG. 4) has two longitudinal rectilinear edges 2 a, 2 b that form an acute angle with each other.

Preferably these two edges form an angle of 20° to 40°.

The strip has two lateral edges 2 c, 2 d which are fitted with winglets 8, 9 respectively, and which are adjacent to these edges and fold up onto the sides 6, 7 of the sole.

The two lateral edges 8, 9 are of unequal width and are not parallel. As a result, the strip has the shape of an irregular quadrilateral whose opposite sides are neither in parallel nor have the same length (FIG. 12). This shape contributes to the retention in position of the strip in spite of the any frontal impacts suffered.

The small winglet 8, located against the left side of the shoe for the right foot 6, is equipped with a hole 10 to allow a pin 11 carried by an extension 12, fixed to the winglet by a hinge 13, to pass through this hole when the extension is folded back onto the winglet (FIGS. 4 to 6). This pin 11 is intended to enter into a dowel 14 that is driven obliquely into the left side 6 of the sole. The pin can be solid or hollow.

In a variant (FIG. 8), the small winglet 8 carries the pin directly 11, which is then equipped with a head 11 b that allows its extraction by hand or with a tool.

The large winglet 9 carries two fixed studs 15, 16 that are intended to enter into corresponding hollow dowels 17, 18 driven into holes in the right side 7 of the sole (FIG. 11).

Preferably, the small winglet 8 is perpendicular to the strip while the large winglet 9 is perpendicular or slanting outwards in relation to the strip (FIGS. 3 and 4). The same comments apply to the strip 3 located under the heel.

Preferably, the sides of the sole against which the winglets of the strip are pressed have flats or recesses which ensure a good contact of the winglets with these sides. In FIG. 12, dashed lines (shown as M) show the position of the flats 6 a, 7 a for the winglets 8, 9 of the strip 2 applied under the forefoot of the shoe for the left foot.

The strips are designed so that the small winglets are facing inwards, that is toward the space between the shoes, so that the user is easily able to start the removal of a strip by resting the corresponding foot on the other knee and then grasping the small winglet in order to extract, from the sole, the fixing pin that carries this extension or, if the winglet has a removable pin, by pulling on the head of this pin to extract the latter from the sole and so detach the winglet from the sole, after which he can lift the strip and extract, from the sole, the studs which were holding the large winglet. These operations can be facilitated if the strip and its winglets have a certain ability to deform.

FIG. 11 is a magnified view of a sole at the location of a ventilation hole 20 of the shoe, which passes obliquely through the sole S and which is fitted with a hollow dowel 17 designed to receive a hollow pin 15 for attaching the winglet 9 of the strip. This is seen only by its head 15 a, visible outside the winglet. The strip and the winglets are preferably made of a thin metal with a thickness of no more than a few millimeters. It is equipped with spikes, striations, etc, depending on the sport to be played. The user can thus have a net of strips allowing the playing of different sports or suitable for a variety of surfaces.

In the previous implementations, the longitudinal edges of the strips are rectilinear. In a variant, these edges can be curvilinear. In fact, the edges are all shaped to facilitate the retention of the strip and its resistance to frontal impacts.

When the edges are curvilinear, the mean axes of the curves form an acute angle with each other, preferably in the range 20° to 40°.

FIGS. 13 to 19 relate to implementation variants.

FIG. 13 shows variants of strips, marked 20 and 30, with their winglets 80 and 90. These strips have curvilinear longitudinal edges.

In addition, in these variants, the large winglet 90 carries two studs 140 designed to be inserted into suitable cut-outs formed on the side of the sole facing outwards (and therefore seen when walking), while the small winglet 80 carries a top claw 141 designed to grip the top of the sole.

Preferably, the strip, for example in nylon or other synthetic material having the desired qualities of resistance to abrasion and a certain flexibility, is created by moulding together with its studs and its claw.

The studs are advantageously fitted with a gripping tab (not shown) which enters with them into the holes in the sole but which can be grasped to extract the stud from the hole in the sole, in a similar manner to the connection blocks used in computer connections. Preferably, recesses are formed on the sides of the shoe in order to accommodate the claws 142.

To fit the strips, the user proceeds as indicated above for the previous implementation, except that after inserting the studs of a strip into the holes provided for this purpose in the sole on one side of the shoe, he pulls on the strip, taking advantage of the flexibility of the strip or of the sole, so as to hook the claw onto the sole on the other side of the shoe (FIGS. 14 and 15).

He then proceeds in a similar manner for the other shoe.

FIG. 15 shows two views of a flat shoe for the right foot PD fitted with a device according to the invention. It can be seen that the studs are located on the winglets on the right side of the shoe facing outwards, while the claws are visible on the left side.

It can be seen in these figures that the longitudinal edges 20 a, 20 b of the strip 20 located under the forefoot are not parallel to each other and form an acute angle with each other. These edges are also oblique in relation to the transverse axis A of the sole (FIG. 15). As a result, these edges have a curvilinear shape which reduces the incidence on the strip of frontal impacts which would tend to shift it.

The same applies to the shoe for the left foot.

The same considerations apply to the case of the bootees (FIGS. 16 to 19).

The invention is not limited to these implementation examples.

Hereafter, another embodiment of the shoe is described with reference to FIGS. 20 to 24.

The ordinary shoe for the right foot PD shown in FIGS. 20 to 24 is equipped with two removable strips 2, 3 under the forefoot 4 and under the heel 5 respectively, surface-mounted on the underside of the sole S. In this description, word “shoe” relates to any kind of footwear.

A front strip 2 is located under the forefoot 4 at some distance from the front end of the sole S. A heel strip 3 is located under the heel end 5 of the sole S.

Preferably, the front strip 2 is located under the forefoot 4 where the head of the metatarsal leans on.

The front strip 2 located under the forefoot (FIG. 22) can have two longitudinal rectilinear edges 2 a, 2 b that form an acute angle with each other. Preferably these two edges form an angle of 20° to 40°.

The front strip 2 has two lateral edges 2 c, 2 d which are fitted with upwardly extending and portions, like winglets 8, 9 respectively, and which are adjacent to these edges and extends uprightly up to the sides of the sole S. The two lateral edges 2 c, 2 d are of unequal width and are not parallel. As a result, the front strip 2 has the shape of an irregular quadrilateral whose opposite sides are neither in parallel nor have the same length. This shape contributes to the retention in position of the strip in spite of frontal impacts suffered.

The front strip 2 located under the forefoot 4 can also be of substantially the same shape as described above but with curvilinear longitudinal edges 2 a, 2 b. In fact, the edges are all shaped to facilitate the retention of the strip and its resistance to frontal impacts.

Each winglet 2 c, 2 d of the front strip 2 carries a male-female engagement portion, like atop claw 81, 91, designed to grip the top of the sole S.

Preferably, male-female engagement portions, like recesses 46, 47, are formed on the sides of the sole S in order to accommodate the claws 81, 91.

A release tab 82 is provided to the winglet 8 on the inner side of the foot on which the shoe is to be put on. The inner side of the foot is the side facing the other foot, i.e. for a right foot, the inner side is its lateral left side and for a left foot, the inner side is its lateral right side. In other words, the release tab 82 extends opposite the corresponding claw 81.

The release tab 82 is shaped so that it can be stepped on with the shoe fitted on the other foot and is physically linked to the claw 81 on the same winglet 8.

Bending downward the release tab 82 releases the corresponding claw 61 (on the same side) from the recess 46 on the side of the sole S.

Preferably, the front strip 2, for example in nylon or other synthetic material having the desired qualities of resistance to abrasion and certain flexibility, is manufactured by being integrally molded with its winglets 8, 9, claws 81, 91 and release tab 82.

When the edges 8, 9 are curvilinear, the mean axes of the curves form an acute angle with each other, preferably in the range 20° to 40°.

The heel strip 3 is shaped to fitly cover the heel part 5 of the sole S, and comprises a plate 31 with the shape of the heel part 5 of the sole S, namely back edge 32 and a front edge 33 (FIG. 23). Both edges 32, 33 may have same concavity or different concavity.

From the back edge 32, a back post 320 extends in substantially upright manner and ends with a male-female engagement portion, like a back claw 321, for fixing the heel strip 3 to the sole S or the shoe. The back claw 321 extends inwardly from the back post 320. A corresponding male-female engagement portion, like a recess 58, in the sole S or the shoe is then provided to receive the back claw 321.

From the front edge 33 of the heel strip 3 an upwardly extending end portion, like a front winglet 330, extends substantially in upright manner and ends with a male-female engagement portion, like a front claw 331 facing inwards, and with a release tab 332 facing outwards. The release tab 332 and the front claw 331 are thus physically connected. The front claw 331 is shaped to cooperate with a corresponding male-female engagement portion, like a recess 59, on the sole S for fixing the heel-strip 3 under the sole S. Once the heel strip 3 fixed under the sole S, it can be removed by bending downward the release tab 332. Bending the release tab 332 releases the front claw 331 from the corresponding recess of the sole.

Preferably, the heel strip 3, for example in nylon or other synthetic material having the desired qualities of resistance to abrasion and certain flexibility, is manufactured by being integrally molded with its winglet 320 and post 310, claws 311, 321 and release tab 332. The back post 320 is preferably stronger than the front winglet 330 and thus less flexible.

The recesses 46, 47, 58, 59 on the side of the sole S ensure a good contact of the winglets and post with these sides.

For fixing the front strip 2 onto the shoe PD, the user just needs to adjust one claw 81 or 91 to the corresponding recess 46 or 47 in the sole S and apply an adequate pressure on the other claw 91 or 81 so that it deforms due to the material flexibility and lodges into the corresponding other recess 47 or 46 in the sole S. Eventually, pulling the front strip 2 is necessary prior to applying pressure.

For fixing the heel strip 3 onto the sole S, the user has to adjust the back claw 321 to the corresponding recess 58 in the sole S or shoe and apply a pressure onto the front claw 331 so that it deforms due to the material flexibility and lodges into the corresponding recess 59 in the sole S. Eventually, pulling the heel strip 3 is necessary prior to applying pressure.

For removing the front strip 2 out from the sole S, the user can use his other foot by stepping onto the release tab 82 causing its downward bending, which releases the claw 81 on the same side from the corresponding recess 46 of the sole S. Thus, he does not need to bend his back or lower himself down. The user can also bend down or lower down and use his hand or any tool to apply pressure on the release tab 82 for causing its downward bending. Then, he pushes sideward to release the other claw 91.

For removing the heel strip 3, the user lifts his foot off the ground and grasps the release tab 332, bends it downwards, thereby releasing the front claw 331 of the heel strip 3 from the corresponding recess 59 in the sole S, then pushes the heel strip 3 backwards to release the back claw 321 from the corresponding recess 59 of the sole S. The user can also just lower himself down, lifts the heel part of the shoe while leaning on the front part of the shoe, grasps the release tab 332 and removes it as mentioned above.

He then proceeds in a similar manner for the other shoe.

The same applies to the shoe for the left foot.

The strips can be covered on their undersides by a suitable material such as gum or leather.

At least one strip can have ground anchoring arrangements, such as studs or spikes, on its underside to turn the shoe into a sports shoe. These studs or spikes can be conical such as those used for football (soccer) shoes. They can also be crenel-shaped and placed on the edges of circles such as those used for golf shoes.

The underside of the strip can also have any suitable design for any use (leisure, sporty, city . . . ).

With the possibility for replacement, the strips 2, 3 can lengthen the life span of the sole S. Indeed, the strips are preferably placed under the sole where friction between the shoe and the ground is most considerable (head of the metatarsal and heel). Thus, almost only the strips are worn-out during use of the shoe and they can be replaced easily.

Covering the whole heel gives the advantage to provide efficient wearing heel strips. Indeed, one individual does not wear out his shoes the same way another one will. Some will wear out the inner side of the heel, others the outer side of the heel. It also provides a larger space for endowing the heel strip with any kind of underside element so that it best suits the activity for which the shoe is aimed at.

The invention is not limited to these implementation examples. 

1. A footwear comprising a sole and a removable device placed under the sole of the footwear, a peripheral region of the sole and the removable device having male-female engagement portions in opposite regions for retaining the removable device under the sole, and at least one of said male-female arrangements being provided on a flexible portion of the removable device and said removable device being provided in the vicinity of said at least one male-female arrangement with a protruding release tab integral with said removable device and which can be selectively moved to cause the deformation of said flexible portion and the disengagement of said male-female engagement portions.
 2. The footwear of claim 1, wherein the removable device is in the form of a strip.
 3. The footwear of claim 2, wherein the strip is a front strip positioned under the forefoot and having two longitudinal edges and two lateral edges which are shorter than the two longitudinal edges, and has end portions extend upwardly from the lateral edges, the male-female engagement portions of the removable device being positioned in the upper region of the upwardly extending end portions.
 4. The footwear of claim 3, wherein the two longitudinal edges are not parallel to each other.
 5. The footwear of claim 3, wherein the release tab extends laterally from the end portion of the lateral edge opposite the other foot when the footwear is worn.
 6. The footwear of claim 2, wherein the strip is a heel strip positioned under the heel and having a back edge and a front edge.
 7. The footwear of claim 6, including upwardly extending end portions from the back edge and the front edge.
 8. The footwear of claim 7, wherein the male-female engagement portions of the removable device are positioned in an upper region of the upwardly extending end portions.
 9. The footwear of claim 6, wherein the release tab extends at the front edge of the removable device toward the front part of the sole.
 10. The footwear of claim 1, wherein the male-female engagement portions are tongue-recess engagement elements.
 11. The footwear of claim 10, wherein the tongue-recess engagement elements on the sole are recesses and tongue-recess engagement elements on the removable device are tongue-shaped claws engaging said recesses.
 12. The footwear of claim 1, wherein the removable device is made integrally from a flexible material.
 13. The footwear of claim 1, wherein the removable device has on its underside ground anchoring arrangements. 